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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Large-scale integration of wind energy into the power system considering the uncertainty information = Elektrituulikute integreerimine energiasüsteemi arvestades informatsiooni mittetäielikkust /

Agabus, Hannes, January 2009 (has links)
Thesis (doctoral)--Tallinn University of Technology, 2009. / Includes bibliographical references.
12

An evaluation of the wildlife impacts of offshore wind development relative to fossil fuel power production

Jarvis, Christina M. January 2006 (has links)
Thesis (M.M.P.)--University of Delaware, 2006. / Principal faculty advisor: Willet Kempton, College of Marine and Earth Studies. Includes bibliographical references.
13

Dynamic modeling, simulation and control of a small wind-fuel cell hybrid energy system for stand-alone applications /

Khan, Mohammad Jahangir Alam, January 2004 (has links)
Thesis (M.Eng.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 115-129.
14

A design methodology for the supply of subterranean water through the use of wind energy

Marais, Brett Richard January 2005 (has links)
Thesis (M.Tech.: Civil Engineering)-Dept. of of Civil Engineering and Surveying, Durban Institute of Technology, 2005 xii, 89 leaves : ill. ; 30 cm / The Reconstruction and Development Programme adopted by the Government of National Unity is more than a list of the services required to improve the quality of life of the majority of South Africans. It is not just a call for South Africans to unite to build a country free of poverty and misery; it is a programme designed to achieve this objective in an integrated and principled manner. Based on the strategic objectives, as highlighted in the White Paper on Water Supply and Sanitation Policy, with regard to alleviating the chronic potable water shortages in South Africa, this thesis investigates a design methodology to supply potable water through the use of wind energy. The design focuses on small rural off-grid developments where grid electricity either has not or will not reach, and where renewable energy is the only viable option. This thesis provides an overview of wind energy and presents the fundamentals of wind power calculations. It also formulates an overview of the historic and present situation with regards to potable water supply, and reflects on the need for urgent intervention. The feasibility of using wind energy to supply potable water to rural communities in South Africa is explored in a case study. The various problem areas are identified and examined and a wide range of possible solutions are recommended. A final flow chart for the system design is proposed, thus ensuring comprehensive design methodology from which future design of similar systems can be based.
15

Methods for short-term prediction of wind speeds in the Pacific Northwest Columbia Gorge wind farm region

Davidson, James D. (James Douglas) 15 June 2012 (has links)
Variable electrical generation (VG) sources such as wind farms are an increasing percentage of total electrical generation in the Bonneville Power Administration (BPA) balancing area and are starting to impact the ability of the regional balancing authority to control the electric grid. Wind farms are not dispatchable and challenge historical electric grid control methods. Successful integration of VG at high penetration levels of wind needs to address increased overall system variability and the rapid power ramp rates caused by wind. One of the new control paradigms needed is accurate wind speed prediction which directly relates to wind farm power output. With an accurate wind speed forecast other generation sources can be dispatched as needed to ensure grid stability. This work uses BPA metrology station (MS) data to make predictions for short-term wind speed where short-term is defined as a one hour prediction horizon. It is shown that, using the available metrology station data and several different prediction methodologies, only small improvements in short-term wind speed prediction can be achieved with the available data for the algorithms analyzed. / Graduation date: 2013
16

Enabling High Wind Penetration in Electrical Grids

Elnashar, Mohab January 2011 (has links)
Wind generation has become one of the most popular choices of technology for adding new generation capacity to power systems worldwide. Several factors have contributed to the increased integration of wind generation, including environmental concerns and the continual increase in fossil fuel prices. As well, recent regulations have moved toward limitations on greenhouse gases, especially in the European Union (EU). Similar laws are currently under consideration in the US and other parts of the world. Other factors have also promoted the use of wind energy, such as advances in manufacturing and control technology and the attractiveness of wind as a “green” source of energy. The large-scale integration of wind power into an electricity system introduces planning and operational challenges because of the intermittent nature of wind speed and the difficulty involved in predicting it. For these reasons, wind energy is often considered an unreliable energy source. Additional problems are associated with the integration of large-scale wind farms into an electrical grid, among which wind power fluctuation is the most challenging. To maximize the penetration level of wind energy in a grid, a reliable technology must be developed in order to eliminate or at least decrease wind power fluctuation. The primary goal of this thesis was to develop methods of maximizing the penetration level of wind energy conversion systems (WECSs) into a grid, which requires mitigating wind power fluctuation. A robust control technique has therefore been developed for mitigating wind power fluctuation. This control technique exploits historical environmental data collected over a number of years in order to evaluate the profile of the output power of a variety of wind energy conversion systems (WECSs). The developed control technique was applied to Types A and C WECSs modifying the pitch angle controller of Type A WECS and the back-to-back converter control of Type C WECS. The Attachment of a storage device to the WECSs after the control technique is applied was investigated from both an economic and a technical point of view. The optimum sizing and siting of the wind energy conversion system equipped with the proposed control technique was also studied. This research is expected to contribute to the advancement of WECS technology by presenting a feasible solution to the problems associated with the integration of large-scale WECSs into electrical grids.
17

Development and performance investigation of a novel solar chimney power generation system

Beneke, Louis January 2015 (has links)
D. Tech. Mechanical Engineering, Mechatronics and Industrial Design / South Africa has limited reserve electricity resources and many parts of the country have limited access to electricity. Electricity production capacity is at maximum and almost each Giga watt is accounted for. Predictions suggest South Africa would have a serious electricity allocation problem in the very near future and current rolling blackout in many of our cities can attest to the looming problem. The energy crisis in South Africa has highlighted the need to increase electricity generation capacity and to search for alternative energy sources. Solar chimney plants could form part of the solution in the near future in South Africa to create additional power. This study aimed to develop a wind generation system in areas where wind is absent. A solar chimney power plant is expected to provide remote areas in South Africa with electric power, or to complement the current electricity grid. Solar energy and the psychometric state of the air are important to encourage the full development of a solar chimney power plant for the thermal and electrical production of energy for various uses. Research within the South African context and particularly on increasing the effectiveness of the solar chimney power plant technology is lacking; as such this study proposes the development of a solar chimney plant and associated technology to ensure the effectiveness of this plant.
18

Analysis of wind energy resource and impact of its integration into power systems

Ayodele, Temitope Raphael. January 2012 (has links)
D. Tech. Electrical Engineering. / Aims to investigate wind resources of a given site and develop a mathematical model that is suited for the selection of an appropriate wind turbine for the site. Develop a mathematical model for a wind energy conversion system (WECS) and its use in studying the behaviour of wind generators in response to the electrical network disturbance. The impact of wind power on the transient stability of a power system and the integration impact of intermittent wind power on the small signal stability of a power system.
19

Optimization of reactive power flow in a wind farm-connected electric power system

Numbi, Bubele Papy. January 2012 (has links)
M. Tech. Electrical Engineering. / One of the main issues in the integration of large wind power generation into the electric power networks is the voltage drop at the point of common connection (PCC) and the increase in power losses as well. This work deals with the optimization of the reactive power control in a power system with integration of a wind farm with the aim of minimizing the total active power losses and improving the load voltage profiles
20

A design methodology for the supply of subterranean water through the use of wind energy

Marais, Brett Richard January 2005 (has links)
Thesis (M.Tech.: Civil Engineering)-Dept. of of Civil Engineering and Surveying, Durban Institute of Technology, 2005 xii, 89 leaves : ill. ; 30 cm / The Reconstruction and Development Programme adopted by the Government of National Unity is more than a list of the services required to improve the quality of life of the majority of South Africans. It is not just a call for South Africans to unite to build a country free of poverty and misery; it is a programme designed to achieve this objective in an integrated and principled manner. Based on the strategic objectives, as highlighted in the White Paper on Water Supply and Sanitation Policy, with regard to alleviating the chronic potable water shortages in South Africa, this thesis investigates a design methodology to supply potable water through the use of wind energy. The design focuses on small rural off-grid developments where grid electricity either has not or will not reach, and where renewable energy is the only viable option. This thesis provides an overview of wind energy and presents the fundamentals of wind power calculations. It also formulates an overview of the historic and present situation with regards to potable water supply, and reflects on the need for urgent intervention. The feasibility of using wind energy to supply potable water to rural communities in South Africa is explored in a case study. The various problem areas are identified and examined and a wide range of possible solutions are recommended. A final flow chart for the system design is proposed, thus ensuring comprehensive design methodology from which future design of similar systems can be based.

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